This invention relates to a mine stopping using a reinforcing brace or truss to resist deflection of the stopping when there is a pressure differential on opposite sides of the stopping. The stopping comprises a plurality of metal panels in side-by-side relation to a least partially close a passage in a mine and can have a door and/or pressure relief structure mounted in the stopping.
Mine stoppings are widely used in mines to impede or stop the flow of air in mine passages. This invention involves a mine stopping of the general type shown in U.S. Pat. Nos. 4,547,094, 4,820,081 and 4,911,577 but includes reinforcement to reduce deflection caused by air pressure differential loading of the stopping. Many of the prior art stoppings were formed from a plurality of side-by-side telescoping panels that extended from floor to ceiling across the width of the mine passage. The panels were secured together and in place in the mine passage, typically adjacent to the entrance of a passage. The stopping was also sealed to the walls, roof and floor if desired.
Some mine passages can be quite large, e.g., 20 feet wide and 10 feet high and even as large as 60 feet wide and 35 feet high. Further, the pressure differential across a stopping can be large. The large pressure differential and/or the large size of the mine passages that a stopping closes can subject the stopping to large forces which causes the stopping to bend or deflect. To reduce this deflection, bracing across the stopping is needed. The bracing can also be used to secure the panels of the stopping together in side-by-side relation. However, current bracing has not been as strong, versatile and simple to use in a mine as one would prefer.
Stoppings can also be provided with one or more doors and/or pressure relief or control means. In stoppings that include one or more doors, some resistance to deflection has been accomplished by using floor to ceiling jacks at positions intermediate the side walls which shortened the span for the bracing reinforcement which helped reduce deflection.
Another of the problems with the use of stoppings in mines is that the mine walls tend to shift over time, generally moving closer together from the weight of the overburden. Likewise, the floor and ceiling move closer together over time. Thus, a requirement for a stopping is to be able to accommodate this change in passage size over time without detrimental effect on the stopping.
Among the several objects of this invention may be noted the provision of improved mine stoppings of the type using a brace for reinforcement against deflection under load; the provision of such a stopping structure that will be effective in at least partially blocking a mine passage from air flow and is easy to install and maintain without excessive attention; the provision of a reinforcing truss for mine stoppings that is versatile in use and easy to install and that will accommodate mine passage size changes without operator attendance; the provision of such a truss that has a variable length to accommodate different sizes of passages and changes in the size of the passage after installation; the provision of such a truss that provides adequate resistance to deflection under load and requires reduced material for construction; the provision of a stopping system that includes a door and a door frame that cooperate with an extensible reinforcing truss that is easy to install and maintain and effective in reducing deflection while eliminating the need for floor to ceiling jacks; and the provision of a reinforcing truss that can be used at a joint between two sets of stopping panels that are in end-to-end relation to reinforce the stopping against deflection and to join the sets of stopping panels in end-to-end relation.
One aspect of the present invention involves the provision of a high pressure stopping system for use in a mine to at least partially block a mine passage. The stopping system includes a plurality of stopping panels positioned side-by-side to form a stopping wall extending between opposite side walls of a mine passage. An elongate brace is provided on a low pressure side of the stopping wall for reinforcing the stopping wall against deflection. The brace includes a central beam and at least one slide member operatively associated with the central beam to provide relative movement therebetween whereby the brace has a variable length.
Another aspect of the present invention includes the provision of a truss for reinforcing a mine stopping system against deflection when under load. The stopping system includes a plurality of stopping panels secured together side-by-side to form a stopping wall for at least partially closing a mine passageway. The truss includes a compression chord that has opposite ends. The chord comprises a central beam having opposite ends and at least one slide member slidably mounted on the central beam adjacent one end thereof. The slide member is movable relative to the central beam for varying the length of the compression chord. A tension chord having opposite ends is secured to the central beam adjacent opposite ends of the central beam. A web extends between the central beam and the tension chord generally at the center of the truss.
The present invention is also directed to a stopping system for use in mines to form a stopping wall to at least partially block a mine passage having side walls. The stopping wall has a normally high pressure side and a normally low pressure side. The stopping system includes a plurality of stopping panels positioned adjacent one another and secured together in side-by-side relation to form a portion of the stopping wall. A door frame defines an opening through the stopping wall and the door frame includes a pair of spaced apart generally vertical columns secured to some of the stopping panels. The door frame also includes a generally horizontal lintel that extends between the columns and is secured to some of the stopping panels. The columns each have a lower end disposed for engagement with a floor of the mine passage at a position between side walls of the mine passage. Each column also has an upper end spaced from a roof of the mine passageway and positioned adjacent a respective end of the lintel and secured thereto. The columns and lintel cooperate to reinforce the wall against deflection under a pressure differential load. At least one door is movably mounted on at least one of the columns and is sized and shaped to at least substantially close the opening.
Another aspect of the present invention involves the provision of a mine stopping system that includes a brace. The brace includes an elongate central beam and at least one slide member operatively associated with the central beam to provide relative movement therebetween whereby the brace has a variable length. The brace is secured to and extends between mine walls of a mine passageway. The system comprises a first set of generally vertical lower stopping panels that are positioned side- greater than bide and have upper and lower ends. A second set of generally vertical upper stopping panels are positioned side-by-side and have upper and lower ends. The upper stopping panels are positioned above the lower stopping panels with the lower ends of the upper panels being positioned adjacent the upper ends of the lower stopping panels. The first and second sets of panels are positioned in the mine passageway and at least partially close the mine passageway. Means is provided for securing the central beam to selected upper and lower stopping panels adjacent the lower ends of the upper panels and the upper ends of the lower panels.
Other objects and features will be in part apparent and in part pointed out hereinafter.